US 6,446,937 B1 · Removable gear drive for mechanical jack

Abstract

A jack assembly for raising and lowering an object such as a trailer. The jack includes telescoping jack tubes which are expanded and contracted through operation of an axial screw. The screw is drivably connected to a gear drive mounted in an upper end of the jack. A crankshaft is supported within the upper end of the jack tube by a pair of end bushings and includes a hexagonal intermediate portion. A first pinion gear having a hexagonal throughbore is drivably mounted to the intermediate portion of the crankshaft. The first gear is in driving engagement with a screw gear connected to the axial screw. At least one of the end bushings is removable to facilitate disassembly of the gear drive. Rotation of the crank transmits rotation to the crankshaft and the first pinion gear in turn transmitting rotation to the screw gear and the axial screw for telescoping movement of the jack.

Claims18

Dependent claims

A selectively extensible jack assembly comprising:

a telescopically adjustable housing having means for controlling the telescoping movement of said housing;
a drive assembly positioned within said housing and drivably connected to said means for controlling the telescoping movement of said housing;
and
a crank operatively connected to said drive assembly;
said drive assembly including a crankshaft supported within said housing, said crankshaft having a portion thereof with a non-circular cross-sectional configuration, a first drive gear drivably mounted to said non-circular portion of said crankshaft, and a second drive gear drivably engaging said first drive gear, said second drive gear connected to said means for controlling telescoping movement of said housing.

2 more elements

Dependencies are inferred from the claim text.

Removable gear drive for mechanical jack

Life of this patent

Removable gear drive for mechanical jack

Life of this patent

Abstract

Claims18